It seems Jay Z may have done something to really piss off his sister-in-law Solange Knowles… but they forgot to get rid of the evidence.

TMZ has secured surveillance footage from an elevator at a Met Gala after-party last week at the Standard Hotel in NYC, which shows Solange screaming at Jay Z before physically attacking him.

In the below clip, Beyonce’s bodyguard holds back a pissed off Solange as she punches and even kicks the rap mogul while his wife Beyonce stands watching. Jay maintained his calmness by only blocking the launches of attacks.

In the above photo, all parties involved were seen leaving the elevator like nothing happened. No word on what triggered the fight. As the trio left the venue, they got in separate cars, Bey and Solange in one, while Jay was gently nudged to get into another.